Cu Nanoparticles Modified Step-Scheme Cu(2)O/WO(3) Heterojunction Nanoflakes for Visible-Light-Driven Conversion of CO(2) to CH(4)

In this study, Cu and Cu(2)O hybrid nanoparticles were synthesized onto the WO(3) nanoflake film using a one-step electrodeposition method. The critical advance is the use of a heterojunction consisting of WO(3) flakes and Cu(2)O as an innovative stack design, thereby achieving excellent performance for CO(2) photoreduction with water vapor under visible light irradiation. Notably, with the modified Cu nanoparticles, the selectivity of CH(4) increased from nearly 0% to 96.7%, while that of CO fell down from 94.5% to 0%. The yields of CH(4), H(2) and O(2) reached 2.43, 0.32 and 3.45 mmol/g(cat) after 24 h of visible light irradiation, respectively. The boosted photocatalytic performance primarily originated from effective charge-transfer in the heterojunction and acceleration of electron-proton transfer in the presence of Cu nanoparticles. The S-scheme charge transfer mode was further proposed by the in situ-XPS measurement. In this regard, the heterojunction construction showed great significance in the design of efficient catalysts for CO(2) photoreduction application.